gistfile1.txt

library(dplyr)
if (getRversion() >= "3.6.0") {
  set.seed(234)
} else {
#  RNGversion("3.5.0")
  set.seed(1)
}
# creating example data
n = 20
ids = 1:n
reps = sample(1:5, size = n, replace = TRUE)
df = tibble(id = rep(ids, reps))
df = df %>%
  group_by(id) %>%
  mutate(visit = 1:n()) %>%
  ungroup() %>%
  mutate(outcome = rnorm(n()))

## bootstrap
# just get the unique IDs
id_df = df %>%
  select(id) %>%
  distinct()

# this bootstrap samples with replacement
boot = id_df %>%
  sample_n(size = n(), replace = TRUE) %>%
  group_by(id) %>% # need to group for mutate below
  mutate(index = 1:n()) %>% # get the index for duplicate number
  arrange(id) # not necessary but let's you see the indices

# join them together, only ids in boot will be kept, but
# will be duplicated because index is unique for each ID
this_boot = left_join(boot, df) %>%
  arrange(id, visit, index)

tidy_bootstrap_repeated.R

library(dplyr)
if (getRversion() >= "3.6.0") {
  set.seed(234)
} else {
#  RNGversion("3.5.0")
  set.seed(1)
}
# creating example data
n = 20
ids = 1:n
reps = sample(1:5, size = n, replace = TRUE)
df = tibble(id = rep(ids, reps))
df = df %>%
  group_by(id) %>%
  mutate(visit = 1:n()) %>%
  ungroup() %>%
  mutate(outcome = rnorm(n()))

## bootstrap
# just get the unique IDs
id_df = df %>%
  select(id) %>%
  distinct()

# this bootstrap samples with replacement
boot = id_df %>%
  sample_n(size = n(), replace = TRUE) %>%
  group_by(id) %>% # need to group for mutate below
  mutate(index = 1:n()) %>% # get the index for duplicate number
  arrange(id) # not necessary but let's you see the indices

# join them together, only ids in boot will be kept, but
# will be duplicated because index is unique for each ID
this_boot = left_join(boot, df) %>%
  arrange(id, visit, index)